I prefer it, but hunted for 30yrs without it. Subdued colors that haven't been washed in brightners should work fine. If you move, animals are going to see you no matter what you wear. Birds, turkeys specifically, can see color, unlike deer/elk which see in shades of gray. I've found that I can wear a camo face mask and while standing still, be totally invisible, to deer and elk, even standing in the open wearing a blaze orange vest that's been treated with UV blocker. Take the mask off though and they see that beacon of a face and they're gone. I snuck up on a cow elk one time during deer season, everytime she'd put her head down, I'd take a couple steps toward her, I had absolutely no cover, but I was wearing full camo face mask and gloves, but also had on a blaze orange vest that is required by law here during any modern firearm season. I got to within 25yds of her and the wind swirled and she was history, but I started my "sneak" from well over 100yds away.